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# Comparing irrational numbers with radicals

Learn how to sort a bunch of numbers (4√2  2√3  3√2  √17  3√3  5) from least to greatest without using a calculator.

## Want to join the conversation?

• At , why is it just answer 17 but at , 5 is 25?
• He is squaring each number. So at he squares the squared root of 17, the square root of 17x the square root of 17 equals 17. The square root of 17 is a number slightly bigger than 4, because 4x4 equals 16, so this is just a little bit more than that.

At he square 5.
5x5=25

The concept is that if you square each number you can compare the numbers without the radical signs........
• how many times did he say square?
• It might be wrong, but I think it was 67 time!

***I counted it all, but it may be inaccurate!***
• I’m confused on what exactly he’s doing. Is he squaring the square roots? Is that it?
• Yes, he is squaring the square roots and when you do this you always end up with the original number. For example: (sq.rt of 4)^2 is equal to 4. He is also squaring the factors being multiplied by the square roots
• I don't know what a radical is. Help plz.
• ching
• how is √17 17?
I searched it up on google and it says the answer is 4.12310562562?
• i got a 3/4 but i got a 0/4
• Wait so 4√2 is that 4 x √2 or like 4√2 (like you know how you can cube/ square but instead there's a 4?) Please help ;-;